In a case where a rider drives the same vehicle in a public road area such as a public road and a non-public road area such as a circuit, the functions of the vehicle can be changed depending on the road area on which the vehicle travels, which becomes more convenient for the rider. Methods of changing the functions of the vehicle include, for example, a method of changing the functions by use of a switch operated by the hand of the rider (e.g., see Patent Literature 1), and a method of changing the functions in which an authentication device attached to the vehicle reads an authentication card or the like.